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Bureau of Mines Information Circular/1985 



Asbestos Availability— Market 
Economy Countries 

A Minerals Availability Program Appraisal 

By T. F. Anstett and K. E. Porter 




UNITED STATES DEPARTMENT OF THE INTERIOR 



75) 

**/NES 75TH A^ 



^Mjartf. a«^«j£]^w. 




Information Circular 9036 



Asbestos Availability— Market Economy Countries 

A Minerals Availability Program Appraisal 

By T. F. Anstett and K. E. Porter 




UNITED STATES DEPARTMENT OF THE INTERIOR 
Donald Paul Hodel, Secretary 

BUREAU OF MINES 
Robert C. Horton, Director 



As the Nation's principal conservation agency, the Department of the 
Interior has responsibility for most of our nationally owned public lands 
and natural resources. This includes fostering the wisest use of our land 
and water resources, protecting our fish and wildlife, preserving the 
environmental and cultural values of our national parks and historical 
places, and providing for the enjoyment of life through outdoor recreation. 
The Department assesses our energy and mineral resources and works to 
assure that their development is in the best interests of all our people. The 
Department also has a major responsibility for American Indian reserva- 
tion communities and for people who live in island territories under U.S. 
administration. 







Library of Congress Cataloging in Publication data: 




Anstett, T. F. (Terrance F.) 

Asbestos availability — market economy countries. 

(Information circular/United States Department of the Interior, Bureau of Mines; 9036) 

Bibliography: p. 21 

1. Asbestos industry. 2. Market surveys. I. Porter, K. E. (Kenneth E.) II. Title. III. Series: 
Information circular (United States. Bureau of Mines); 9036 



TN295.U4 
[HD9585.A65] 



622 s 
[338.2'7672] 



85-600063 



For sale bv the Superintendent of Documents, U.S. Government Printing Office 
Washington, DC 20402 



<-n 



in 



- 






PREFACE 



The Bureau of Mines is assessing the worldwide availability of nonfuel critical 
minerals. The Bureau identifies, collects, compiles, and evaluates information on ac- 
tive, developed, and explored mines and deposits and mineral processing plants 
worldwide. Objectives are to classify domestic and foreign resources, to identify by cost 
evaluation resources that are reserves, and to prepare analyses of mineral availability. 

This report is paft of a continuing series of reports that analyze the availability 
of minerals from domestic and foreign sources. Questions about these reports should 
be addressed to Chief, Division of Minerals Availability, Bureau of Mines, 2401 E St., 
XW.. Washington. DC 20241. 






CONTENTS 



Page 

Preface iii 

Abstract 1 

Introduction 2 

Acknowledgments 2 

Characteristics and uses 2 

Substitution 3 

Environmental hazards, standards, and problems . 3 

Production and consumption 4 

World 4 

United States 4 

Production and consumption outlook 5 

Prices 5 

Geology of asbestos deposits 6 

Property discussion 6 

Australia 7 

Brazil 8 

Canada 8 

Colombia 9 

Cyprus 9 

Greece 9 

Italy 9 



Page 

Mexico 9 

Republic of South Africa 9 

Swaziland 10 

United States 11 

Zimbabwe 11 

Mining, milling, and transportation- 
methods and costs 11 

Mining 11 

Milling 13 

Transportation 14 

Evaluation methodology 15 

Availability 16 

Chrysotile, grade 3 16 

Chrysotile, grade 4 17 

Chrysotile, grade 5 17 

Chrysotile, grade 6 18 

Chrysotile, grade 7 19 

Amosite and crocidolite 19 

Availability summary 20 

Conclusions 20 

References 21 



ILLUSTRATIONS 

1. Minerals Availability Program evaluation procedure 2 

2. Asbestos production. 1973-83 4 

3. Classification of mineral resources 6 

4. Location map. Thetford Mines area properties 8 

5. Location map, southern African properties 9 

6. Location map. northern Cape crocidolite properties 10 

7. Total availability, grade 3 chrysotile 16 

8. Annual availability, grade 3 chrysotile 16 

9. Total availability, grade 4 chrysotile 17 

10. Annual availability, grade 4 chrysotile 17 

11. Total availability, grade 5 chrysotile 18 

12. Annual availability, grade 5 chrysotile 18 

13. Total availability, grade 6 chrysotile 18 

14. Annual availability, grade 6 chrysotile 18 

15. Annual availability, grade 7 chrysotile 19 



TABLES 



1. Quebec standard grades and uses of asbestos 3 

2. Estimated 1983 world asbestos capacity and production 4 

3. January 1982 producer prices 5 

4. Property resource information. January 1982 7 

5. Mining methods, production, and costs 12 

6. Average total operating cost for selected countries 12 

Market distribution of asbestos producers 14 

8. Estimated mill to market fiber transportation costs 15 

9. Chrysotile availability summary 20 



VI 



UNIT OF MEASURE ABBREVIATIONS USED IN THIS REPORT 



in 


inch 


km 


kilometer 


km 2 


square kilometer 


m 


meter 


mm 


millimeter 



t 


metric ton 


$/t 


dollar per metric ton 


t/h 


metric ton per hour 


t/yr 


metric ton per year 


yr 


year 



ASBESTOS AVAILABILITY— MARKET ECONOMY COUNTRIES 
A Minerals Availability Program Appraisal 

By T. F. Anstett 1 and K. E. Porter 2 
ABSTRACT 



The Bureau of Mines evaluated the potential availability of chrysotile, amosite, and 
crocidolite asbestos from 42 properties in market economy countries. This resulted in 
the development of tonnage-cost relationships indicating the quantity of grades 3 through 
7 asbestos at various average total costs of production at 0% and 15% rates of return 
on invested capital. The availability of grades 2 and 8 was also evaluated, but since 
each is produced at only one property, no analytical results were given. 

Total demonstrated recoverable chrysotile fiber potentially available of grades 3 
through 7 from the 42 properties evaluated follow: 1.59 million t, 21.00 million.t, 16.74 
million t. 15.54 million t. and 19.27 million t, respectively. The total amount of crocidolite 
is 1.69 million t. 

Owing to the good potential for discovery and development of new deposits, long- 
term availability of fiber of all three types is not in jeopardy. However, many of the 
crocidolite properties evaluated in the northern Cape crocidolite field of South Africa 
have relatively small demonstrated resources, and new deposits will have to be exploited 
by the late 1990's to sustain projected levels of production. 

1 Geologist. 

2 Mining engineer. 

Minerals Availability Field Office. Bureau of Mines, Denver, CO. 



INTRODUCTION 



The Bureau of Mines has undertaken this study assess- 
ing the availability of asbestos, a commodity that has com- 
mercial value for use in various industrial applications. This 
report addresses the availability of asbestos from 36 foreign 
and 6 domestic properties in terms of its average total cost 
of production over the life of each property evaluated. An 
outline of the procedure followed for this evaluation is 
shown in figure 1. 

The main purpose of this study is to present an estimate 



of the amount of fiber of various types and grades that is 
potentially available from the most important producing 
and undeveloped properties in market economy countries. 
The results of this study are presented in the form of total 
and annual available curves, which show the amount of 
fiber, by grade, that could be produced from each property 
evaluated. The curves plot availability against average total 
cost of production over the estimated life of each property. 



ACKNOWLEDGMENTS 



Production and cost data for domestic properties ana- 
lyzed in this study were developed at Bureau of Mines Field 
Operations Centers in Denver, CO, Juneau, AK, Spokane, 
WA, and Pittsburgh, PA. Production and cost data for all 
other properties were collected through a Bureau contract 



with International Mineral Services Associates, Golden, 
CO, under the direction of Tom Pool, project manager. 
Robert Clifton, Bureau of Mines commodity specialist, is 
also acknowledged for his assistance in the preparation of 
this report. 



CHARACTERISTICS AND USES 



Asbestos is a term applied to six naturally occurring 
minerals that are exploited commercially for their desirable 
physical properties which are in part derived from the 
asbestiform habit. These minerals are the serpentine 
mineral chrysotile and the amphibole minerals grunerite 
asbestos (also referred to as "amosite"), riebeckite asbestos 
(also referred to as "crocidolite"), anthophyllite asbestos, 
tremolite asbestos, and actinolite asbestos. Individual 
mineral particles, however processed and regardless of their 
mineral name, are not considered to be asbestos if the length 
to width ratio is less than 20 to 1. 

The characteristics that render this group of minerals 
commercially important include their fibrous structure, ten- 



sile strength, fiber length, and resistance to high- 
temperature and chemical attack. Chrysotile is the most 
important commercially, accounting for over 95% of world 
consumption (1, p. 55). 3 Only chrysotile, crocidolite, and 
amosite have any significant commercial importance. 

On the basis of use, asbestos falls into two principal 
classes: spinning and nonspinning fiber. Spinning fiber com- 
prises the longer grades of chrysotile and crocidolite; 
nonspinning fiber includes the shorter lengths of these 
varieties and all lengths of amosite. For some uses, fiber 



3 Italized numbers in parentheses refer to items in the list of references at 
the end of this report. 



Identification 

and 

selection 

of deposits 



L 



Tonnage 

and grade 

determination 



Engineering 
and cost 
evaluation 



Mineral 

Industries 

Location 

System 

(MILS) 

data 

i 

MAP 

computer 

data 

base 



Deposit 

report 

preparation 



MAP 

permanent 

deposit 

files 



Taxes, 

royalties, 

cost indexes, 

prices, etc... 



Data 

selection and 

validation 



Variable and 

parameter 

adjustments 



Economic 
analysis 



Data 



Availability 
curves 



Analytical 
reports 



Sensitivity 
analysis 



Data 



Availability 
curves 



Analytical 
reports 



Figure 1 .—Minerals Availability Program evaluation procedure. 



characteristics must meet stringent standards. For others, 
fibers of varying quality and character may be satisfactorily 
used. 

The main use of asbestos is in the manufacture of con- 
struction materials, primarily in the form of asbestos 
cement pipe and sheet, flooring products, and roofing prod- 
ucts. Other major end uses are in friction materials, paper, 
coatings and compounds, packing and gaskets, textiles, and 
plastics. In the United States, the construction sector ac- 
counted for 42^ of total asbestos consumption in 1982. 
However, friction products represented the single largest 
use. 21% of total 1982 domestic consumption (2). 

For purposes of product grading, the major industry 
standard was developed by the Quebec chrysotile asbestos 
industry, whereby asbestos is classified and valued accord- 
ing to fiber length, from the longest (No. 1) to the shortest 
(No. 9\ Table 1 shows the major grading specifications and 
general product uses by grade classification. 

To some extent, grades (i.e., fibers of differing lengths) 
are interchangeable, and much research effort has been 
devoted to substitution of more abundant (shorter) grades 
for less plentiful I longer). For example, in the early days, 
Canadian grades 3 and 4 were used exclusively in cement 
production. However, owing to the advent of more 
sophisticated fiber preparation techniques and incorpora- 
tion of blue (crocidolite) asbestos in the mixture, it has been 
possible to use shorter grades of chrysotile in cement prod- 
ucts. This is possible because of the high tensile strength 
and "dewatering" characteristics of the crocidolite fiber. 



Table 1.— Quebec standard grades and uses of asbestos 



Grade 

Long fiber: 

No. 1 crude 
No. 2 crude 
No. 3 

Medium fiber: 

No. 4 

No. 4 

No. 6 

Short fiber: 



Length 
specifications, mm 



Uses 



»19 
9.5-19 
6-9 5 



3-6 
3-6 



<3 



Textiles. 

Textiles; insulation. 

Textiles; packing; brake 
linings; clutch facings; 
electrical, high-pressure, 
and marine insulation. 

Asbestos-cement pipe. 

Asbestos-cement pipe and 
sheets; moulded pro- 
ducts; paper products; 
brake lines and gaskets. 

Asbestos-cement products; 
brake linings and 
gaskets; plaster; 
backing for vinyl sheets. 



No. 7 


<3 


Moulded brake linings and 
clutch facings; plastics; 
filler in vinyl and asphalt 
floor tiles, asphalt 
compounds, and calking 
compounds; paints and 
drilling mud additives. 


No 8 


(') 


Do. 


Very short fiber: 






No. 9 


V) 


Rock ballast; asphalt 
paving aggregate; 
landfill. 



'Weight specifications. 
Source: (1, p. 58; 3). 



SUBSTITUTION 



Owing to the particularly sensitive issue regarding 
possible health hazards associated with the use of asbestos, 
a concerted effort has been directed at finding or develop- 
ing substitute materials for asbestos fiber. 

For many years, asbestos has enjoyed a virtual monop- 
oly in the markets in which it is used. Efforts to develop 
economically and practically viable substitutes have met 
with varying degrees of success. The following examples in- 
dicate the advance of development of viable alternative 
materials for many uses currently filled by asbestos. In the 
paper products market, a number of alternative materials, 
including aramid. carbon, and graphite, have been tried 



with a reasonable degree of success. In roofing applications, 
alternatives include organic felt and fiberglass felt. 
Fiberglass appears to be the main alternative to asbestos 
in textile uses, although certain ceramic fibers, polymers, 
and carbon are also competitive. Perhaps the principal area 
in which substitute materials have not made a significant 
impact is in asbestos cement sheet and pipe. Because these 
products constitute the single most important market sec- 
tor by volume for the asbestos industry, if a viable and 
economically competitive alternative emerges, given the 
present climate of opinion regarding the asbestos industry, 
survival of the industry could be severely jeopardized. 



ENVIRONMENTAL HAZARDS, STANDARDS, AND PROBLEMS 



The serious health hazards associated with in- 
discriminate handling of asbestos fiber from mineral extrac- 
tion to fabrication have long been recognized by the asbestos 
industry. It is generally accepted that, for the three prin- 
cipal types of commercially used asbestos, there is a greater 
risk of contracting lung cancer or mesothelioma when ex- 
posed to crocidolite than to amosite, and that less risk is 
associated with chrysotile than with either of the other two 
types. A definitive assessment of the risks associated with 
each fiber type does not currently exist and would be ex- 
tremely difficult to develop, but the general consensus to 
date is that crocidolite is considerably more carcinogenic 
than chrysotile <4, p. 26). 

Despite the paucity of medical and scientific evidence 
relating to the health risks associated with various levels 
of exposure to asbestos fiber, there is a high level of con- 



cern within the consumer sector. Probably the most con- 
troversial aspect of the asbestos and health problem is the 
claim that even brief exposure may be harmful. In July 
1983, the U.S. Environmental Protection Agency (EPA) 
notified its intention to propose a ban on the use of asbestos 
in products such as cement pipe, roofing material, and floor 
coverings. Additionally, the agency will write proposed 
regulations placing a maximum on the amount of asbestos 
used for all other products and establish a timetable for 
phasing out all but a few minor uses over the next few years 
(5, p. 89). Asbestos cement products comprise the most im- 
portant use of asbestos in the construction and building in- 
dustry (which asbsorbs about 70 r /r of total asbestos produc- 
tion worldwide). If fiber used for cement products were 
banned, the result would almost certainly be the demise 
of the asbestos industry. 



PRODUCTION AND CONSUMPTION 



Detailed information regarding production and con- 
sumption of individual fiber grades by country is difficult 
to obtain. The following information represents readily 
available data on world production and consumption of 
fiber. North American (United States and Canadian) data 
are presented in more detail. Although separate figures for 
production and consumption are not available on a world 
or individual country basis for most countries, a common 
assumption is that, over the long run, total world produc- 
tion and consumption are in balance. 



WORLD 

Estimated 1983 world asbestos production and 
capacities are shown on table 2. Total world asbestos fiber 
production was 3.92 million t. This figure represents ap- 
proximately 59% of total world capacity. The leading pro- 
ducer was the Soviet Union which, at 2.20 million t, ac- 
counted for 56% of total world production, with output at 
72% of estimated capacity. Canada was second in terms of 
total production at 0.82 million t, followed by the Republic 
of South Africa at 0.2 million t. Both countries produced 
at only about half of capacity during the year (54% for 
Canada, 48% for the Republic of South Africa). 

Chrysotile accounts for approximately 95% of world 
asbestos production, crocidolite, 3%, and amosite, 1.5%, with 
the remaining 0.5% from other fiber types (e.g., an- 
thophyllite, tremolite). The Republic of South Africa is the 
only country to produce fiber of all three primary types and 
is the only international commercial source for both 
crocidolite and amosite. In 1982, South African production 
by fiber type was as follows: crocidolite, 49% chrysotile, 33%; 
amosite, 18% (7, p. 154). 

Figure 2 shows world and Canadian asbestos produc- 
tion for 1973-83. Over that period, shipments from Cana- 
dian mines averaged approximately 30% of total world pro- 
duction. This percentage is lower than the 45% average dur- 
ing the previous 10-year period (1963-72). Over the 1973-83 
period, Canadian production ranged from a high of 39% in 
1973 and 1974 to a low of 19% in 1982. Canadian shipments 
thus have shown a steady decline as a percentage of world 
production over the past 20 yr. 

The Republic of South Africa exports about 93% of its 
production. However, the country's asbestos industry is be- 
ing hurt by competition not only from traditional producers 



Table 2.— Estimated 1983 world asbestos capacity ana 
production 

Country or region Capacity, Production, Production as °/o 

10 6 t 10M of capacity 

Canada 1.51 0.82 54 

China .30 .10 33 

Europe 1 .36 .16 44 

Republic of South Africa . .42 .20 48 

Other Africa 2 .34 .24 71 

South America 3 .21 .10 48 

Soviet Union 3.05 2.20 72 

United States 11 .07 64 

Other 30 .03 10 

Total 6.60 3.92 59 

includes Cyprus, Greece, Italy, and Yugoslavia, 
includes Swaziland and Zimbabwe, 
includes Brazil and Colombia. 
Source: (4, p. 19; 5, p. 88; 6, p. 13). 



6,000 



5,000 - 



4,000 



3,000 - 



2,000 



1,000 - 



p 

CO 800 



, World production 




'Canadian production 




600 



500 



400 



200 



100 



US. imports 





U.S. production 



/U.S. exports 



1973 1975 1977 1979 1981 

Figure 2.— Asbestos production, 1973-83. 



I983 



such as Canada, the United States, and Zimbabwe, but also 
from asbestos imports that are entering the world market 
for the first time from Brazil and Greece. Consequently, 
crocidolite production has been reduced to about 65% of 
capacity. At the time of this writing, only the three largest 
and most productive crocidolite mines are in operation: Pom- 
fret, Klipfrontein, and Elcor (5, p. 89). 

World consumption has not declined as dramatically as 
has consumption in North America and Western Europe. 
In fact, until recently, consumption of fiber has been ris- 
ing approximately 4.4% annually in developing nations, 
largely owing to rapid growth in construction activity. 



UNITED STATES 

Figure 2 shows production from the United States, 
which is a relatively insignificant world producer, account- 
ing for less than 2% of world fiber production. U.S. produc- 
tion grew substantially during the 1960's, peaked at 
136,000 t in 1973, and subsequently declined by more than 
50% to 64,000 t in 1982 and an estimated 70,000 t in 1983. 



Over the same period, exports of fiber from the United 
States grew, to a high of 64.000 t in 1981. Although U.S. 
net import reliance was 651- in 1983 (6). over 851 of U.S. 
production was exported and about 951 of U.S. consump- 
tion was supplied by foreign producers. 

Canada is the leading source of fiber for the U.S. market, 
supplying 951 of all fiber imported by the United States. 
This proportion has varied little over the past 10 years. The 
Republic of South Africa accounts for less than 4% of U.S. 
imports, primarily in the form of crocidolite fiber. 

Of U.S. imports by fiber type, 961 is chrysotile, 3% is 
crocidolite. and 11 is amosite. Nearly half (49%) of U.S. im- 
ports in 1974-83 was grade 7, 281 of which was used in 
flooring products, and another 481 was grades 4 through 
6. the primary use of which was in asbestos-cement pipe 
and sheet. Canada relies heavily on the United States as 
a market for its exports, and the United States over the past 
10 years accounted for an average of 351 of Canadian 
shipments. However, the U.S. share declined from 42% in 
1973 to 271 in 1981 and 1982. Although the United States 
has become less dependent upon Canadian fiber, the rate 
of decline in U.S. consumption of Canadian fiber has been 
slower than the rate of decline of total U.S. imports over 
the past 10 yr (fig. 2). 

In terms of U.S. consumption by fiber grade over the 
past 10 years, the most dramatic decline has come in the 
longer grades. Short fiber (grades 6 and 7) constituted 62% 
of consumption in 1974 and 841 in 1982. In recent years, 
U.S. consumption of asbestos friction materials and 
asbestos-based coatings and compounds has remained 
relatively stable. The products ban being considered by the 
EPA would have a proportionately larger impact on con- 
sumption of longer fiber, especially in the case of asbestos- 
cement pipe. If the ban is put into effect, the U.S. market 
would be principally for short fiber. 



PRODUCTION AND 
CONSUMPTION OUTLOOK 

In terms of the future trend of asbestos use, industrial- 
ized countries can be expected to gradually reduce consump- 
tion. The European Economic Community has indicated its 
desire to implement substitutes as they become viable. 
Sweden and Denmark have already passed laws banning 
asbestos, and Japan has passed a law requiring reduction 
of asbestos in asbestos-cement products to 5% maximum 
content. 

The trend in industrialized countries is toward replace- 
ment of asbestos. In addition, the developed countries con- 
stitute a "mature" market which, regardless of the health 
issue surrounding asbestos, could not be expected to pro- 
vide for substantial future growth in consumption. By con- 
trast, the developing countries can be expected to account 
for the major growth in world demand, especially for fiber 
used in construction materials such as asbestos-cement pipe 
and sheets. Also, environmental and health standards will 
almost certainly continue to be less stringent in develop- 
ing countries than in developed countries. 

A critical deterrent to increased asbestos consumption 
in developing countries could be their la'ck of hard currency 
and sometimes precarious financial situations. Although 
the technology to produce asbestos-cement products is 
relatively inexpensive and not as complex or capital inten- 
sive as technologies for other building materials that could 
compete with asbestos products, developing countries have 
shown a limited ability to increase their technological 
capabilities and can be expected to rely heavily on foreign 
technology for the foreseeable future. However, the ability 
of these countries as a group to finance the acquisition of 
this assistance is in doubt. 



PRICES 



Prices of asbestos fiber are normally negotiated, and the 
details are seldom available publicly. Absolute prices of a 
particular grade fiber may vary widely, depending on the 
market forces relative to supply and demand. However, pro- 
ducer 'or "posted") prices, which, until recently, were quoted 
on a regular basis by some asbestos producers, indicate that 
the price ratios among the various fiber grades have been 
fairly constant through time. Depending on market condi- 
tions, contract prices may vary considerably from producer 
prices; it is generally acknowledged that, during the past 
few years of slack demand, considerable discounting relative 
to posted prices has occurred. 

The f.o.b. mine, Quebec, prices established by a major 
asbestos mining company acting as price leader historically 
generally set the pattern for world asbestos prices. There 
are approximately 29 different fiber grades (classes) and 
subclasses in the Quebec Asbestos Mining Association stan- 
dard classification, and within each class there can be 4 or 
5 different varieties. Differences between fiber from dif- 
ferent ore bodies and mines can result in price premiums 
or discounts from list prices, depending upon supply and 



demand and the quality and utility of each grade. Accord- 
ingly, fiber bearing the same designation by grade or 
subclass, but having different physical or chemical 
characteristics, may be sold at different prices. 

The January 1982 posted prices presented in Asbestos 
magazine (8) quoted from Quebec producer price lists were 
used as the basis for comparing the cost of production for 
the evaluated properties. Those prices, in terms of dollars 
per metric ton of fiber, are shown in table 3. 



Table 3.— January 1982 Quebec producer prices (8) 

Fiber Price, 

grade $/t fiber 

2 2,435 

3 1,478 

4 974 

5 547 

6 386 

7 175 

8 74 



GEOLOGY OF ASBESTOS DEPOSITS 



Most chrysotile deposits are located in serpentinized 
ultramafic (peridotite) bodies. In the important producing 
Thetford Mines area of eastern Quebec, Canada, the fibrous 
form of serpentine is found in veinlets, mostly less than 1 
in wide, in dark green massive serpentine. The veinlets and 
wall rock have the same chemical composition and vary only 
in physical character. The chrysotile occurs as silky fiber, 
referred to as cross fiber when oriented perpendicular to 
the walls of the veinlet and as slip fiber when more or less 
parallel to the vein walls. Of the two, cross fiber is much 
more common. 

Of special interest in terms of geological characteristics 
of chrysotile asbestos deposits is the origin of the fiber- 
bearing veinlets. The three main possibilities include (1) 
veinlets are replacement of wall rock, (2) veinlets are fissure 
filling, and (3) the fiber began to crystallize in minute frac- 
tures so tight that they could be bridged by the first formed 
crystals and wall rocks were subsequently pushed apart as 
fiber growth occurred. Of the three hypotheses, the last is 
the one most commonly accepted by geologists. 

Among exceptions to the general geologic occurrence 



(i.e., serpentine hosted) of chrysotile described above are the 
Arizona deposits, represented in this study by the El Dorado 
property. The Arizona chrysotile deposits are among the few 
known occurrences in which the enclosing serpentine was 
not derived from an ultrabasic rock, but from limestone. 
The Precambrian Mescal Limestone has been intruded by 
diabase sills which provided mineralizing solutions that 
have serpentinized certain limestone beds. Chrysotile oc- 
curs as cross fiber veinlets parallel to bedding. 

Among the amphibole asbestos deposits, only those in 
the northern Cape and northern Transvaal Provinces of 
South Africa constitute an important resource. The South 
African deposits occur with banded ironstone of the 
Transvaal Supergroup. Both the crocidolite deposits, located 
in the northern Cape, and amosite deposits (northern 
Transvaal) are situated within the banded ironstone, 
although separated by over 600 km. This lateral persistence 
is evident within the banded ironstone itself, in which in- 
dividual bands, even those a fraction of a millimeter in 
thickness, can be traced for several kilometers without a 
perceptible change. 



PROPERTY DESCRIPTION 



Evaluation of the 42 properties was performed on 
resource values sufficiently defined to be considered 
demonstrated according to the definitions established by 
the Bureau of Mines and Geological Survey (9) and shown 
in figure 3. Resource estimates for some properties were 
available from published data, but several were obtained 
directly from company personnel or other confidential 
sources. 

Table 4 contains resource and other pertinent informa- 
tion relating to properties evaluated for this study. Only 
five properties (Slate Creek, Abitibi, Penhale, Roberge Lake, 



and Pegaso) are undeveloped (i.e., have never produced). 
These properties contain 11.0 million t of demonstrated 
recoverable fiber. Six properties (El Dorado, Christie, 
Midlothian, Danielskuil, Riries, and Senekal) that had pro- 
duced in the past but were inoperative at the time of this 
evaluation, are identified as past producers (PP) on table 
4. Woodsreef, Australia, is currently producing at a reduced 
level, anticipating a possible return to full production in 
1985. Because the operation has not been fully shut down, 
Woodsreef has been classified as a producer for this 
evaluation. 



Cumulative 
production 


IDENTIFIED RESOURCES 


UNDISCOVERED RESOURCES 


Demonstrated 


Inferred 


Probability range 


Measured 


Indicated 


Hypothetical | Speculative 




ECONOMIC 


Res 


erve 


Inferred 

reserve 

base 


1 

+ 

+ - 
1 


MARGINALLY 
ECONOMIC 


ba 


se 


SUB- 
ECONOMIC 




1 





Other 
occurrences 



Includes nonconventional and low-grade materials 



Figure 3. — Classification of mineral resources. 



Table 4.— Property resource information, January 1982 



Property name 



Owner 



Status' 



Type 1 



Fiber 
grades 



Fiber 
type 3 



Recoverable 
fiber 4 



Demonstrated 

recoverable liber 

10 3 



United S:a:es 

Alaska Slate Creek 

Arizona: El Dorado 

California 
Calaveras 
Christie 
Santa Rrta 5 

Vermont Lowell 

Total US 
Australia Woodsreef 
Brazil: Cana Brava 



Canada 
Abrtibi 

Asbestos Hill 
Baie Verte 
Bell 
Black Lake 

British Canadian 

Carey Canada 

Cassia- 

Jeffrey 

King- Beaver 

Midlothian 

National 

PenhaJe 

Roberge Lake 

Total Canada 
Colombia Las Bnsas 
Z .z-s ~- a-::; 
Greece Zidani 
Hah/: Baiangero 
Mexico Pegaso 
South Africa 

Danietskml 

Elcor 

Emmarentia 



~-r" Zr 



Rines 

Wandrag 
m teba* 



Total South Africa 
Swaziland Havekx* 
Zimbabwe 

Gain s 

King 

Shabanie 

Total Zimbabwe 
Grand total 



Tanana Asbestos Corp and GCO Minerals 
Jaquays Mining Corp 



Calaveras Asbestos Corp 

Tenneco Oil Co 

Union Carbide 

Vermont Asbestos Company, Inc 

Woodsreef Mines Ltd 

S A Mineracao de Amianto 



Abitibi Asbestos & Brinco Ltd 
La Soc Nat de I'Amiante 

Baie Verte Mines. Inc 

La Soc Nat de I'Aminate 
Lac d'Amiante du Quebec Lte 
United Asbestos Corp Ltd. 
La Soc Nat. de I'Amiante 

Jim Walters Corp 

Brinco Mining Ltd 

Johns-Manville Canada Inc. 
La Soc Nat de I'Amiante 

United Asbestos Inc. . 

Lac d'Aminate Quebec Lte 
La Soc Nat de I'Amiante 
McAdam Mining Corp Ltd 



Minera Las Bnsas S.A 

Cyprus Asbestos Mines Ltd 

Asbestos Mines of Northern Greece 

Amiantifera di Baiangero SpA 

Cia. Minera Pegaso S.A 



General Mining Union Corp 

... do 

Lonhro Ltd 

General Mining Union Corp. 

do 

do 

do 

do 

do 

Lonhro Ltd 

General Mining Union Corp 



N 


S 


4 


Ch 


PP 


U 


3.4,7 


Ch 


P 


s 


4.5,6 


Ch 


PP 


S 


7 


Ch 


P 


s 


7 


Ch 


P 


s 


3.4.5,6.7 


Ch 


P 


s 


4,5.6 


Ch 


P 


S 


4,5.6 


Ch 


N 


U 


4,5.6.7 


Ch 


P 


c 


4.5,7 


Ch 


P 


s 


4,5,6 


Ch 


P 


U 


3.4,5,6,7 


Ch 


P 


s 


3.4,5,6.7 


Ch 


P 


s 


3,4,5,6,7 


Ch 


P 


S 


4.5,6.7 


Ch 


P 


c 


3.4,5,6 


Ch 


P 


c 


4,5.6.7 


Ch 


P 


c 


3.4.5,6.7 


Ch 


PP 


s 


4,5,6.7 


Ch 


P 


s 


3.4,5,6,7 


Ch 


N 


u 


3,4,5,6,7 


Ch 


N 


S 


5,6,7 


Ch 


P 


s 


4,6 


Ch 


P 


s 


3.4 


Ch 


P 


S 


4,5,6 


Ch 


P 


s 


4,5,6,7,8 


Ch 


N 


s 


5,6,7 


Ch 


PP 


u 


3,4 


Cr 


P 


u 


3.4 


Cr 


P 


u 


3.4 


Cr 


P 


u 


3.4 


Cr 


P 


u 


4.5,6,7 


Ch 


P 


u 


3,4 


A 


P 


u 


3,4,6 


Cr 


PP 


u 


3,4 


Cr 


PP 


u 


5,6,7 


Ch 


P 


u 


3.4 


Cr 


P 


u 


3.4 


Cr 



Turner & Newall. Ltd and the Swazi nation 



Turner & Newall, Ltd 
do 
.do 



4.5 



Ch 



c 


4.5 


Ch 


u 


4.5 


Ch 


u 


2,3.4.5,6 


Ch 



3.1864 
37 

278 3 

788.3 

2,926.4 

534.7 

7.717.8 

4825 

3.621 5 



1,679.4 


1,132.9 


1,046.3 


1,084.0 


3,299.6 


1,834.2 


3,021.3 


1,986.0 


17,954.9 


3,712.8 


3.625.4 


9833 


1.173.4 


2.8188 


45.352.3 


362.9 


565.2 


3.7066 


5.198.4 


2.1850 




703 


728.5 


50.2 


224.1 


532.2 


802.1 


391.5 


40.0 


87.4 


61 8 


1238 



3,111.9 
217.8 

449.6 
2,2820 
2,842.6 

5,5742 
78.096 1 



'Status P — producer PP— past producer. N — nonproducer 
Type U— underground. S — surlace. C — combined methods 

-ysne ch — chrysotile. Cr— crocidolrte 
'Recoverable fiber grouped into following ranges 

A < 1.9% E 8.0%-9.9% 

B 2 0%-3 9% F 10 0%-11.9% 

C 4.0%-5 9% G > 119% 

D 6 0%-7 9% 
'includes 126 yr production at current annual rate of approximately 23.000 t/yr Total resources in the New Idna intrusive are virtually unlimited 



AUSTRALIA 

The Woodsreef property at Barraba merits special men- 
tion because Woodsreef Mines Ltd., in conjunction with ICI 
Australia Ltd., has developed and patented a method for 
wet processing of asbestos fiber. A special problem with the 
Woodsreef fiber is that it does not release as readily from 
the ore or fiberize (i.e., separate or open up) as easily as fiber 
from other producing areas, so that, with the dry milling 
process, a high percentage of fiber "dives" through the 
screen meshes and reports to the tails. Woodsreef is expected 
to be converted to the wet process in 1985, provided the 



necessary financing can be obtained. The prototype mill has 
been operational since January 1982 and is reportedly pro- 
ducing the forecast recoverable grade of 6% fiber, compared 
with 2.7 c /r with the dry process (10). 

Because costs relating to the wet process are uncertain 
and the process has not been developed on a commercial 
scale, the property was evaluated using the dry process. 
However, should the wet process become fully operational, 
the overall recovery will be substantially improved, and the 
total amount of recoverable fiber from the Woodsreef deposit 
will be higher than the total shown on table 4. 
Woodsreef fiber is transported by truck and rail to 



Newcastle, from where it is transported by ship to the 
following destinations in the accompanying approximate 
percentages as of 1981: Australia (6%), Japan and Korea 
(23%), Africa (5%), Southeast Asia (40%), Middle East (4%), 
Pakistan (18%), and North America (4%). 



BRAZIL 

Cana Brava produces approximately 140,000 t/yr of 
grades 4 through 6 fiber, 90% of which is used internally, 
with the remainder exported to Argentina and Venezuela. 
The operation supplies 95% of the total asbestos consumed 
in Brazil and can be expected to continue operating for more 
than 25 yr at the present production level. 



CANADA 

Canadian properties evaluated for this study contain 
more than 45 million t of recoverable demonstrated fiber. 
Except for fiber produced at Asbestos Hill, which is sent 
as ungraded concentrate to the Nordenham mill in West 
Germany for final treatment, all fiber from Canada is milled 
and graded within the country to the final stage for direct 
use in manufactured products. 

Eight of the Canadian properties evaluated are in the 
important Thetford Mines asbestos region of eastern 
Quebec, an area which typically accounts for over 80% of 
annual Canadian production. Chrysotile exports from 
Canada account for 65% of total world exports of that fiber 
type, and shipments from Canada accounted for nearly half 
of estimated 1983 market economy country production (21% 
worldwide) of all fiber types; therefore, the importance of 
the Quebec producers cannot be understated. 

The eight eastern Quebec properties evaluated are Bell, 
Black Lake, British Canadian, Carey Canada, Jeffrey, King- 
Beaver, National, and Penhale (fig. 4). All but Penhale are 
producers. All occur within the serpentine belt of Quebec, 
where serpentinized peridotite and pyroxenite occur as 
sheetlike stocks, dikes, and sills. Together, the eight eastern 
Quebec properties account for 75% of Canadian 
demonstrated recoverable fiber included in this study. 

Most overseas shipments of fiber from Quebec are made 
in the form of 17.5-short-ton containers, which are trucked 




Figure 4.— Location map, Thetford Mines area properties. 



to Montreal and then shipped to their overseas destination. 
The majority of Quebec asbestos is delivered to the follow- 
ing major consuming centers: North America (38%), Europe 
(25%), Asia (20%), and Latin America (10%). 

Among producing Canadian properties, Jeffrey has been 
the most important historically and accounts for 40% of 
demonstrated resources in all Canadian properties 
evaluated. At full production, Jeffrey is the largest asbestos 
producer among market economy countries. The property 
produces fiber in grades 4 through 7. Present production 
is exclusively by open pit, but the operation might go 
underground when open pit reserves are exhausted, prob- 
ably by the mid-1990's. The property was evaluated under 
this assumption. Jeffrey was recently acquired by J. M. 
Asbestos, Inc., from the Manville Corp. and has produced 
as much as 660,000 t/yr. Recently, however, production has 
been about 270,000 t annually, the figure used in this 
evaluation. 

Baie Verte Mines, Inc., a wholly owned subsidiary of 
Transpacific Asbestos, Inc., has reactivated the Baie Verte, 
Newfoundland, mine after acquiring it from Advocate 
Mines in September 1982. The mine produced 40,000 t in 
1983 and planned to increase production to 60,000 1 in 1984. 
Transpacific is reportedly planning to implement the wet- 
milling process that is being developed for the Woodsreef, 
Australia, operation (5, p. 88). Transpacific is part owner 
in that operation. 

The Cassiar operation of Brinco in British Columbia is 
currently an open pit mine, but there are tentative plans 
to go underground by the early 1990's when open pit 
reserves are expected to be exhausted. For this study the 
property has been evaluated based on this development 
plan. Cassiar asbestos is trucked to Stewart, British Colum- 
bia, then barged to North Vancouver from where it is sold 
and distributed to the following major destinations: Asia 
(24%), Europe (29%), North America (21%), and Australia 
(13%). 

Asbestos Hill in northern Quebec is an open pit opera- 
tion with only a few years of reserves remaining at the pres- 
ent pit designed capacity. The mine was closed in 1984 after 
operating at half capacity (25,000 to 35,000 t/yr) in 1983. 
The Asbestos Hill shutdown also resulted in closure of 
Asbestos Corp.'s Nordenham mill in the Federal Republic 
of Germany (5, p. 88). For purposes of this evaluation, full 
capacity production was assumed, continuing as an 
underground operation in 1986. 

The present King-Beaver operation is an amalgamation 
of several mining operations dating from the early days Gate 
1800's) of asbestos mining in the Thetford Mines area of 
eastern Quebec. The operation exploits a series of ore bodies 
extending over an area of 2,130 m by 760 m to a depth of 
nearly 400 m from the surface. At a production peak of 
about 200,000 t/yr in the late 1970's, about a third of the 
total ore mined came from the underground (King) mine. 
At full capacity, about two-thirds of ore from the King- 
Beaver combined operation is sent to the Normandie mill 
and the remainder to the British Canadian #2 mill, both 
within 15 km of the King-Beaver operation. When the King 
(underground) mine is terminated by about 1986, the Nor- 
mandie mill is expected to be used exclusively by the 
Penhale property (currently a nonproducer). All ore 
produced by the Beaver (open pit) mine would then be 
treated at the British Canadian mills. These plans have 
been included as part of this evaluation. 

Among nonproducers, Abitibi and Roberge Lake, both 
in Quebec (although not in the Thetford Mines area), 



together account for 6% of Canadian demonstrated 
recoverable fiber. The Abitibi property would produce fiber 
in the intermediate range (grades 4 through 7). for which 
it would face competition from several current producers. 
A number of feasibility studies have been carried out, with 
early concepts favoring mining by open pit. However, ow- 
ing to the high expense of glacial overburden removal 
i which varies from 18 to 27 m). the most likely mining 
method would be underground. This option was assumed 
for purposes of this evaluation. Roberge Lake (also known 
as Chibougamau) would be mined by open pit. 

The Canadian properties, including nonproducers, have 
all been extensively drilled. The nonproducers are those 
that have been widely reported in the literature and have, 
for the most part, been examined in great detail, both 
geologically and from an economic standpoint. They are the 
properties most likely to begin production in the near 
future. However, given the widespread occurrence of 
favorable host rock (e.g.. the Precambrian shield areas of 
Ontario, the ultramafic belt of the western provinces), and 
the lack of detailed exploration resulting from complex 
geology and extensive glacial cover (e.g., Abitibi), there is 
a high degree of likelihood that more asbestos deposits re- 
main to be discovered in Canada. 



COLOMBIA 

Production began in 1981 from a small open pit mine 
at Las Brisas at a rate of 5,400 t/yr of fiber. Production 
reached 7.000 t yr in 1983, with plans to produce 10,000 
t in 1984. Expected capacity is 25,000 t/yr, but a target date 
to reach that level has not been set (5, p. 88). The operation 
ships its entire output of grades 4 and 6 fiber to Eternit's 
cement plant in Medellin. Colombia. 



CYPRUS 

Amiandos has an annual capacity of 35,000 t/yr of fiber, 
although production has been less in recent years (18,952 
t in 1982 '. At full capacity (assumed for this evaluation), 
the property could produce until the late 1990's. Resources 
at lower levels of probability than demonstrated have not 
been determined, but it is known that there are other 
asbestos occurrences in the area. Apparently, though, only 
the Amiandos Mine area has fiber of sufficient continuity 
to justify exploitation at this time. Fiber is trucked to 
Limassol. from where it is transported to various consumers 
in Europe and Southeast Asia. 



GREECE 

The Zidani operation began production in 1981, with 
a design capacity of 100,000 t yr of fiber. Depressed market 
conditions and technical problems, however, have kept pro- 
duction below that level. Production in 1983 was about 
35,000 1. Plans were to increase output to 55,000 1 in 1984, 
but it is not known when the operation will reach full 
capacity (.5, p. 89). 

At production capacity (assumed for this evaluation), 
the mine can produce for nearly 40 yr, supplying approx- 
imately I5 r r to 20'/ of its output to the domestic cement 
industry ill, p. 66). The mine produced 35.000 t in 1983, 
of which significant amounts were exported to Western 



Europe, Eastern Europe, the Middle East, and the Far East. 
Sales from Zidani are cutting into traditional Canadian 
markets in the Mediterranean and European regions, since 
transportation costs from Greece are lower than from 
Canada (5, p. 89). 



ITALY 

Balangero, also referred to as San Vittore, is the leading 
producer of asbestos fiber in Europe, with production 
reaching a maximum of 165,000 t in 1976. During the past 
few years, though, production has been about 130,000 t/yr. 
The mine is highly mechanized and has the highest pro- 
ductivity of any asbestos mine in the world. Demonstrated 
recoverable fiber has been calculated at over 5 million t to 
a depth of 180 m below the present pit bottom, with addi- 
tional resources below that level. Most (60%) of the fiber 
produced at Balangero is consumed domestically; the re- 
mainder is shipped to Europe and western Asia. 



MEXICO 

The Pegaso property, also referred to as the Papalo 
deposits, had a 1-t/h pilot plant operating between March 
1979 and August 1982. Apparently, there are no firm plans 
to bring the operation into production in the near future. 
If and when the property does come into production, it will 
be by open pit. For this evaluation, the property has been 
modeled to begin producing in 1987. 



REPUBLIC OF SOUTH AFRICA 

The asbestos deposits of South Africa occur in three 
separate geographic areas, each containing different types 
of fiber (fig. 5). Amosite and crocidolite (blue asbestos), the 
two amphiboles, are produced from the northern Transvaal 
and northern Cape Provinces, respectively. Chrysotile is 
produced from the Barberton district of the eastern 
Transvaal. The only amosite (northern Transvaal) property 
evaluated is Penge, which is the only operating mine in the 
amosite field in what was once an extensive mining area 




Figure 5.— Location map, southern African properties. 



10 



of many small operations. Msauli, a producer, and Senekal, 
a past producer, are the two chrysotile properties evaluated. 
The remaining eight properties produce crocidolite from the 
northern Cape field. Amianthus, although a crocidolite pro- 
ducer, had only a few years of life remaining as of the date 
of this study (January 1982), so it was deleted from the 
study. Bute, a recent past producer, has also been excluded 
because its reserves have been nearly exhausted. 

Of the 11 South African deposits evaluated, all but Em- 
marentia and Wandrag are owned by the Griqualand Ex- 
ploration and Finance Co. Ltd. (Gefco), whose parent com- 
pany is General Mining Union Company Ltd. The two 
others are owned by Lonhro Ltd. through subsidiaries. 
Through a sequence of several acquisitions between 
January 1979 and December 1981, Gefco has become the 
major amphibole asbestos producer in South Africa, account- 
ing for 90% of crocidolite production, which it blends with 
the remaining 10% from the Emmarentia and Wandrag 
properties into its products. Gefco is the sole selling agent. 

The principal destinations of crocidolite fiber are Italy, 
the United States, the Middle East, and the Far East. Ex- 
act destinations by proportion are not known, but transpor- 
tation costs for Gefco fiber were available and were used 
for this evaluation. Although Duiker Exploration (Lonhro's 
Emmarentia and Wandrag Mines) sells to Gefco at its Riries 
mill, fiber product distribution and Gefco costs were 
assumed for these properties. 

The northern Cape field produces crocidolite from 
banded ironstones which are exposed in a north-south- 
trending syncline (the Dimoten Syncline) that is 470 km 
long and 40 km wide at its widest area in the south. Both 
limbs of the syncline have been folded into monoclines with 
dips generally at 6°. The deposits are located in the 
monoclinal or basinlike structures situated on either limb. 
Crocidolite development is related to the structures such 
as north-south folds, domes, and basins with subtle changes 
in dip. The greatest development of fiber occurs where two 
sets of folds intersect to form domes or basins. Deposits often 
show a sharp contact at the structure and fade out in values 
away from it. 

Crocidolite reefs have a maximum width of 15 m, 
averaging 4 m. Most of the major operations are based on 
extraction from a number of small or medium-sized deposits 
(e.g, Pomfret, Whitebank, Riries), but some (e.g., Klipfon- 
tein) produce from a single continuous deposit. Where opera- 
tions are based on multiple deposits, they are separated by 
1 km or less. 

The crocidolite deposits of the northern Cape are com- 
monly divided into five geographical areas (fig. 6). The 
areas, with properties evaluated in this study (included in 
parentheses following the name of the area), are Danielskuil 
(Danielskuil, Emmarentia, Klipfontein), Kuruman (Elcor, 
Riries, Wandrag, and Whitebank), Pomfret (Pomfret), 
Koegas (none), and Postmasburg (none). 

Kuruman is presently the most important district in the 
production of crocidolite. All mining to date has been car- 
ried out on the east limb of the Dimoten Syncline. The Pom- 
fret Field is believed to have a large potential because 
known deposits are relatively large and of high grade, but 
thick sand cover and poor outcrop exposure render discovery 
of additional deposits a difficult task. Fiber deposits on the 
west limb of the Dimoten Syncline in the Postmasburg Field 
are largely undeveloped. Past production has been from a 
number of small, near-surface deposits and outcrop work- 
ings scattered throughout the district. A group of medium 
to large, high-grade (10% to 12%) deposits have been 







Figure 6.— Location map, northern Cape crocidolite 
properties. 



outlined near the center of the district but have not been 
developed. However, the district is thought to have con- 
siderable potential for development in the future. 

In the Danielskuil District, only the area surrounding 
the town by that name has been prospected and mined to 
any significant extent. Klipfontein is the most prominent 
known deposit in the district. Very little is known about 
the development potential of the southern half of the 
district, although there is considered to be a good potential 
for deposits in structurally favorable sites. 

Deposits in the Koegas area tend to be low grade, are 
generally deep seated (up to 500 m below the surface), and 
owing to narrow stoping widths (1 m), must be mined by 
labor-intensive hand methods. A major producer in the area 
was the Koegas Mine, which is now closed. 

The northern Cape field accounted for 200,966 1 of fiber 
in 1978; production has declined, owing primarily to market 
conditions, to about 112,00 t in 1982. Total annual produc- 
tion from crocidolite operations evaluated in this study is 
about 150,000 t/yr, averaged over the remaining lives of 
those properties. This includes the two past producers, 
Danielskuil and Riries, with combined annual production 
potential of 22,000 t. 



SWAZILAND 

The Havelock underground mine is in Swaziland near 
the Transvaal boundary, across which the Msauli deposit 
of South Africa is located (fig. 5). The ore body has been fully 



11 



delineated, and all reserves are classified as measured. 
Turner & Newall owns 60*7 of the property and operates 
the mine under a lease from the Swazi nation which is due 
to expire in 1986. Msauli fiber is transported by truck to 
railhead, railed to port at Maputo, Durban, and Port 
Elizabeth, and shipped in the following percentages to 
Japan (65%). Europe (25%), and South America (10%). 



UNITED STATES 

The estimated 1983 production of 70.000 t of asbestos 
in the United States accounted for 2^ of world production 
and 4*7 of output from market economy countries (6). Of 
the six properties evaluated, three are producers: Lowell, 
which is located along the Appalachian fold belt in Vermont 
and produces from a deposit that is similar geologically and 
mineralogically to those in the eastern townships of Quebec; 
and Santa Rita and Calaveras in California. 

The Lowell operation produces chrysotile from an open 
pit mine on Belvidere Mountain in Vermont. The operation 
has a fiber capacity of about 38,000 t yr, but annual out- 
put has been 25,000 t or less since 1977. For this evalua- 
tion, it was assumed that annual production would be ap- 
proximately 28,000 t of fiber. Resource figures were based 
on the assumption that mine life will be 20 yr from the date 
of this analysis. 

Calaveras was the first asbestos mine in California, with 
production as early as 1904. It has been operated con- 
tinuously as an open pit since 1975 by the present owner, 
Calaveras Asbestos Corp., producing grades 4, 5, and 6. 

Santa Rita and Christie (a nonproducer) are located in 
a 145-km 2 mass of serpentinized peridotite (the New Idria 
intrusive* near the southern end of the Diablo Range in 
Fresno and San Benito Counties. The intrusive is quite 
literally a mountain of slip-fiber chrysotile asbestos, averag- 
ing more than 507 fiber locally (12). Only grade 7 fiber is 
present, but the resource potential is, for all practical pur- 
poses, limitless. The demonstrated resource figures used in 
this evaluation apply only to the legal boundaries of the 
two properties evaluated, and only to the extent to which 
the fiber resource has been demonstrated (drilled). For this 



evaluation, 126 yr of production potential have been 
included for the Santa Rita deposit. 

The El Dorado property, shut down since January 1982, 
is typical of the Arizona chrysotile deposits in that it is of 
small tonnage but contains relatively long fiber (grades 3 
and 4, as well as 7) with low iron content. The property must 
be mined underground and employed hand sorting to avoid 
hauling waste the long distance (about 60 km) to the mill. 
The operation was economically viable for many years 
before its closure in 1982. 

A potentially important undeveloped chrysotile deposit 
(Slate Creek) is located in a remote part of Alaska, contain- 
ing approximately 3 million t of fiber. For this evaluation, 
the property was assumed to produce 100,000 t/yr of grade 
4 fiber as an open pit operation. It has been reported {13) 
that the deposit also contains fiber in grades 5 through 7, 
although a percentage breakdown was not available at the 
time of this study. 

The Slate Creek fiber would probably be transported by 
truck and rail to Seward, AK, and then shipped to Seattle, 
WA, where it would be sold. 



ZIMBABWE 

The Zimbabwean properties, Gath's, King, and 
Shabanie (fig. 5), are all underground producers owned and 
operated by Shabanie and Mashaba (Pvt) Ltd., a subsidiary 
of Turner and Newall, Ltd. Presently, the combined pro- 
duction capacity from the mines is 250,000 to 300,000 t/yr 
of fiber, based on capacity of the new mills at Mashaba and 
Shabanie. This production level is expected to be sustained 
through the end of the century. Production from Shabanie 
and Mashaba's operations is significant since they account 
for 50% of the world's textile fiber production (4, p. 33). 
Shabanie Mine, in fact, is the only deposit evaluated in this 
study that produces a significant amount of grade 2 (spin- 
ning grade) fiber. 

All Zimbabwean fiber is transported by rail to Maputo, 
Port Elizabeth, or Durban for distribution to the following 
areas in the accompanying proportions: Japan (20%), United 
States (47%), Europe (20%), and South America (13%). 



MINING, MILLING, AND TRANSPORTATION— METHODS AND COSTS 



Following is a presentation of mining, milling, and 
transportation methods and costs associated with the 
various producing or proposed operations evaluated. In- 
cluded in this discussion are several assumptions that were 
used to evaluate the properties. 

Operating costs and capital investments for the ap- 
propriate mining, milling, and transportation methods were 
obtained or estimated for each deposit. In most cases, ac- 
tual costs were available from published material, company 
personnel, other persons familiar with the operation, or a 
confidential, unpublished source 'e.g., feasibility study). 

The total operating cost is a combination of direct and 
indirect costs. Direct costs include direct and maintenance 
labor, materials, payroll overhead, and utilities. Indirect 
operating costs include administrative costs, facilities 
maintenance and supplies, research, and technical and 
clerical labor. 

Capital expenditures were calculated for exploration, 
acquisition, development, and mine and mill plant and 



equipment. Capital expenditures for mining and milling 
facilities include the costs of mobile and stationary equip- 
ment, construction, engineering, infrastructure, and work- 
ing capital. 

Mining method, annual capacity (average over the re- 
maining life of each deposit), and ranges for mining and 
milling costs are shown in table 5. Weighted-average total 
operating cost (mine plus mill) for selected countries is 
shown on table 6. Operating costs are in terms of dollars 
per ton of recoverable fiber, averaged over the life of each 
property. Owing to the proprietary nature of cost data, only 
a general range can be shown for each property, but 
weighted average costs for countries with several proper- 
ties were included in table 5. 



MINING 

Of the 42 properties evaluated, 19 do or could produce 



12 





Table 5. 


—Mining methods, production, and January 1982 operating costs 






Av Recoverable fiber 1 


Property name 


Mining method Fiber grade production, Mine Mill 

10 3 t/yr 



United States: 

Alaska: Slate Creek 
Arizona: El Dorado . 
California: 

Calaveras 

Christie 

Santa Rita 

Vermont: Lowell 



Open pit 

Room and pillar 

Open pit 

... do 

...do 

...do 



Australia: Woodsreef 
Brazil: Cana Brava . . 



. . do 
. . do 



Canada: 

Abitibi 

Asbestos Hill . . . 

Baie Verte 

Bell 

Black Lake 

British Canadian 
Carey Canada . . 

Cassiar 

Jeffrey 

King-Beaver 

Midlothian 

National 

Penhale 

Roberge Lake . . 



Open stope 

Open pit; sublevel cave . . 

Open pit 

Block cave 

Open pit 

... do 

... do 

Open pit; sublevel stope . 

Open pit; stope 

Open pit; block cave 

Open pit 

... do 

Block cave; modified cave 
Open pit 



Colombia: Las Brisas 
Cyprus: Amiandos . . 
Greece: Zidani 



Open pit 

. . . do . . 



Italy: Balangero 

Mexico: Pegaso 

South Africa: 
Danielskuil . 

Elcor 

Emmarentia 
Klipfontein . 

Msauli 

Penge 

Pomfret . . . 

Riries 

Senekal . . . 
Wandrag . . 
Whitebank . 



Swaziland: Havelock 

Zimbabwe: 

Gath's 

King 

Shabanie 



do 
do 
do 



Room and pillar; semishrinkage stope . 

Room and pillar 

Room and pillar; semishrinkage stope . 

Cut and fill 

Sublevel cave 

Breast stope 

Room and pillar 

... do 

Sublevel stope 

Room and pillar 

... do 

Sublevel cave; shrinkage stope 



Open pit; cave; shrinkage stope 

Panel retreat cave 

Prebreak cave 



4 
3,4,7 

4,5,6 

7 

7 

3,4,5,6,7 

4,5,6,7 

4,5,6 



106.2 
.7 

20.9 
21.9 
23.2 
28.1 

53.6 

139.3 



4,5,6,7 


93.3 


D 


4,5,7 


87.1 


D 


4,5,6 


61.5 


D 


3,4,5,6,7 


67.7 


B 


3,4,5,6,7 


150.0 


B 


3,4,5,6,7 


87.3 


B 


4,5,6,7 


143.9 


A 


3,4,5,6 


90.3 


B 


4,5,6,7 


272.0 


B 


3,4,5,6,7 


142.8 


B 


4,5,6,7 


172.6 


A 


3,4,5,6,7 


89.4 


A 


3,4,5,6,7 


78.2 


B 


5,6,7 


97.2 


B 


4,6 


8.9 


B 


3,4 


35.3 


B 


4,5,6 


97.5 


A 


4,5,6,7,8 


130.0 


A 


5,6,7 


75.3 


A 


3,4 


11.7 


D 


3,4 


33.1 


B 


3,4 


1.3 


B 


3,4 


18.7 


B 


4,5,6,7 


66.5 


B 


3,4 


42.2 


B 


3,4,6 


55.9 


B 


3,4 


10.0 


C 


5,6,7 


5.0 


B 


3,4 


7.7 


B 


3,4 


15.5 


B 


4,5 


31.1 


C 


4,5 


22.5 


D 


4,5 


99.2 


B 


2,3,4,5,6 


135.4 


C 



1 Cost ranges for mine and mill: 

A <$199 

B $100-$199 

C $200-$299 

D $300-$399 



E $400-$499 

F $500-$599 

G $600-$699 

H >$700 



Table 6.— Average total operating cost for selected countries 





Country 


Weighted average cost 
of recoverable fiber, $/t 




Mine Mill 


United States 




107 226 


Canada 

South Africa . 




157 141 
1 52 1 54 


Zimbabwe . . . 




233 112 



by typical open pit methods. The mines are highly mecha- 
nized. Eighteen produce exclusively by underground 
methods, and the remaining five either produce by combin- 
ed open pit and underground simultaneously, or are cur- 
rently operating by open pit and expected to convert to 



underground. This latter category includes Asbestos Hill, 
Cassiar, and Jeffrey, all in Canada. King-Beaver (Canada) 
and Gath's (Zimbabwe) currently produce about half by open 
pit and half by underground methods. 

In terms of annual production averaged over the lives 
of all properties evaluated, open pit mining accounts for 1.8 
million t/yr of fiber (61.6% of the total average annual pro- 
duction from all deposits). All but 0.5 million t is from opera- 
tions that were producing at the time of this evaluation 
(January 1982). The combined (open pit and underground) 
operations with percentage of annual production (average 
over the remaining life) from open pit follow: Asbestos Hill 
(27%), Cassiar (45%), King-Beaver (94%), Jeffrey (19%), and 
Gath's (53%). The underground (King) portion of the King- 
Beaver operation is expected to be phased out by 1986, after 
which only the Beaver open pit will be in operation. For 



13 



this evaluation. Asbestos Hill. Jeffrey, and Cassiar have 
been assumed to convert from their present open pit method 
to strictly underground operations in the future. Gath's is 
the only property evaluated that is expected to continue as 
a combined open pit and underground operation through 
the property's life. 

The methods used in asbestos mining are largely dic- 
tated by the geological occurrence, type, strength, and other 
physical characteristics of the host rock. Selection of min- 
ing method must recognize ore body value and fiber length 
distribution, extent and value of dilution zone, rock mass 
classification, contaminants, and fiber degradation. In- 
discriminate selection of mining method can result in high 
ore loss, high dilution, and expensive support maintenance 
costs. 

Mining methods employed at the properties evaluated 
for this study are shown in table 5. With the exception of 
the El Dorado and northern Cape crocidolite operations, 
whose unique geological occurrences have resulted in 
unique mining methods for asbestos deposits, asbestos pro- 
ducers use mining methods that are similar to those used 
in operations exploiting other minerals. 

Canadian asbestos occurs in irregular veins or veinlets 
in massive serpentinite deposits that are extensive both 
laterally and vertically, so that large-scale, highly 
mechanized open pit methods have been extensively 
employed. A relatively recent development in Canadian 
asbestos mining was block caving, which was found to be 
the most economical underground method. It was first in- 
troduced at the King Mine and is now the only mining 
method employed at Bell. Caving methods are also widely 
used in the Zimbabwean mines. 

Crocidolite operations in the northern Cape of South 
Africa have typically consisted of a number of small 
underground mines using highly labor intensive methods 
to provide hand-sorted ore to feed centrally located mills. 
The present trend is toward less labor intensive operations. 
Three major mining methods have been used by the Cape 
operations: room and pillar, semishrinkage stoping, and 
post pillar with hydraulic fill 'cut and fill). Among these 
methods, room and pillar is used by large producers as it 
lends itself to mechanization, and the wide stopes (4 to 6 
mi allow the use of large, efficient underground machinery- 
The method results in nearly 94% recovery once the pillars 
are "skinned" to measure 1.5 by 1.5 m. Semishrinkage is 
used in conjunction with room and pillar at Danielskuil and 
Emmarentia. Cut and fill is used at Klipfontein, allowing 
for 9C> extraction of ore at that operation. 

All properties in the low mine-cost range (A range, table 
5 1 are open pit operations. Additionally, most of the prop- 
erties in this range have high grades (i.e., greater than 7% 
recoverable fiber). Properties in the low mine-cost range 
with high grades include Christie, Santa Rita, Cana Brava, 
Carey Canada, and Midlothian. Zidani has a low grade 'less 
than 3% i but benefits from low labor costs. Pegaso, in Mex- 
ico, also benefits from low labor costs. Balangero is a highly 
mechanized, efficient operation with productivity among the 
highest of all asbestos producers. 

The weighted average mining cost for U.S. properties 
is the lowest of those countries whose averages are shown. 
All but one U.S. property 'El Dorado, a past producer) are 
open pit. and the average mining cost is influenced to a large 
degree by the Christie and Santa Rita (California) opera- 
tions, which employ front-end loaders to mine high-grade 
asbestos-bearing material. 

Among properties in cost range B '$100/t to $199/t fibf-n 



are most of the Canadian and South African producers. The 
weighted average mine operating cost for South African 
crocidolite properties is $142/t recoverable fiber; cost, for 
Canadian properties is $157/t. Although all of the South 
African crocidolite operations are underground, they have 
high grades, averaging 8.7%; the lowest grade among 
crocidolite properties is greater than 6% . In addition to their 
high grades, the South African operations are highly 
mechanized. Among Canadian properties in this cost range 
are those that currently produce or are projected to produce 
by the relatively inexpensive underground block caving 
method. These include Bell, which produces strictly by block 
caving; Cassiar, which currently produces by open pit but 
which is projected to utilize caving methods when it goes 
underground; and King-Beaver, which utilizes open pit 
(Beaver) and block caving (King). By 1986, only the Beaver 
open pit has been modeled to be in operation. 

Among relatively high-cost operations, Abitibi, a non- 
producer, would be an underground operation (open stope) 
with low grade. Asbestos Hill, although presently an open 
pit operation, is projected to go underground in the near 
future. Baie Verte, although an open pit mine, is projected 
to have a high stripping ratio (4.6:1), which contributes to 
its relatively high mine cost. It also has a low grade (less 
than 4% recoverable fiber). Danielskuil is a past 
underground producer in South Africa with the lowest 
recoverable fiber grade of all crocidolite properties. 
Semishrinkage stoping is used in conjunction with room and 
pillar mining at Danielskuil, which contributes to its 
relatively high mine cost. Although the Gath's mine ac- 
quires half of its production by open pit, the grade is less 
than 4%. Woodsreef and El Dorado are the highest mine 
cost properties evaluated. Woodsreef s recoverable grade is 
very low (2.7%) but would improve (to 6%) if the wet proc- 
ess were installed (10), resulting in a lower cost than that 
shown. El Dorado's grade is more favorable, but it was a 
small, labor-intensive operation. 



MILLING 

The concentration process for asbestos is unique in that 
it involves separation of a fibrous mineral from a massive 
form of the same mineral. Thus, neither chemical composi- 
tion nor specific gravity can be used as the basis for separa- 
tion, which is done strictly by mechanical means. 

A most important principle governing asbestos milling 
is separation of fiber from host rock with a minimum of fiber 
breakage. This is because the value depends largely on the 
fiber length. Modern mills are designed to remove the fiber 
by aspiration (air suction) after each crushing process so 
that destruction of fiber is minimized. 

Essentially, all dry milling processes are very similar, 
relying exclusively on mechanical processes to separate and 
recover fiber. Asbestos milling consists essentially of coarse 
crushing, drying, and recrushing in stages, each step 
followed by screening and air separation of fiber from rock. 
Exceptions are the northern Cape crocidolite operations 
where, owing to the abrasive nature of the banded ironstone 
that hosts the fiber, all mines employ manual sorting of 
underground ore. Run-of-mine ore is passed over a 10-mm 
screen, with the coarse fraction reporting to a sorting plant 
where 3Q7c to 407c of the total mine feed is hand-sorted to 
waste. Run-of-mine ore containing 87c, to 11% fiber is 
upgraded to a mill feed averaging between 11% and 16%, 
depending on sorting efficiency. 



14 



In 1978, the design capacity of all crocidolite plants was 
approximately 200,000 t/yr. Presently, however, the policy 
is to operate only the most efficient plants, and their design 
capacity totals approximately 144,000 t/yr. 

Woodsreef Mines Ltd. has operated a pilot plant wet- 
process mill since January 1982. Little is known about the 
process, except that it has improved the recovery of Woods- 
reef fiber from 2.7% with the dry process to about 6%. The 
Santa Rita operation in California also utilizes a wet proc- 
ess in part of its milling plant, but the particular details 
of that process are not widely available. Besides improv- 
ing recovery of fiber from certain deposits, an especially 
promising aspect of wet mill processing is that it lowers fiber 
dust levels in the workplace. This is a particularly impor- 
tant concern in the mining and processing of asbestos. 

Among properties in mill cost range A (less than $99), 
all have high grades, greater than 7% recoverable fiber. 
Because most milling processes are quite similar, cost is 
largely a function of recoverable fiber grade and labor costs. 
However, mill efficiency can be an important factor. At 
Woodsreef, for example, where the short fiber has a ten- 
dency to "dive" through the classifying screens in the dry 
mill, the effective mill recovery is only about 60%, compared 
with an estimated recovery of nearly 100% with the wet 
process (5, p. 89). Thus, the Woodsreef mill cost is high in 
relation to that of other properties evaluated. The mill 
operating costs for 26 of the 42 properties evaluated occur 
within the $100 to $199 (B) range, indicating that the mill- 
ing process varies little among the properties. 

The weighted average mill cost for Canadian properties 
is $141/t recovered fiber, compared with $155/t for South 
African properties, suggesting that the relatively high cost 
associated with hand sorting of ore at South African prop- 
erties is largely offset by the corresponding mill feed grade 
increase resulting from that process. 



TRANSPORTATION 

For most properties, transportation of fiber from the mill 
is by truck, usually to the nearest railhead, from where the 
fiber is transported to the nearest port if it is meant for 
overseas consumption. In some cases, such as the Las Brisas 



operation in Colombia and Cana Brava in Brazil, where rail 
links are limited, transportation to point of use is solely by 
truck. The Cana Brava fiber is trucked to the major con- 
suming center of Rio de Janeiro, a distance of nearly 
1,500 km. The Cassiar property in extreme northern British 
Columbia, Canada, must transport its fiber by truck to 
Stewart, BC, then by barge to Vancouver, BC, from where 
it is distributed by rail (New York) or ship (Japan, Europe) 
to its destination. 

The two most important asbestos-producing centers are 
the Thetford Mines area in eastern Quebec, Canada, and 
the northern Cape crocidolite field in South Africa. Thet- 
ford fiber is trucked to Montreal or Toronto, from where 
it is shipped by freighter to its various overseas destina- 
tions. Some fiber is railed directly to the United States. 
Specially designed 16-t containers are used to improve 
handling efficiency and minimize possible health hazards 
associated with exposure to fiber. Fiber transportation from 
the northern Cape crocidolite field in South Africa is by 
truck to railhead at either Vryburg or Lime Acres, and by 
rail 800 to 1,100 km to Port Elizabeth. The fiber is then 
transported by ocean freighter to foreign markets. Table 
7 shows market distribution of fiber from general locations 
of producing properties evaluated that export a significant 
percentage of their production. The distribution pattern can 
vary substantially from year to year; however, the distribu- 
tion pattern shown reflects the general export situation at 
the time of this evaluation. 

Transportation costs play a major role in the marketing 
of asbestos. In many cases, the transportation cost deter- 
mines the destination for fiber, especially in the case of 
higher grades (i.e., lower value fiber). Transportation costs 
to major importing regions for important exporting coun- 
tries with properties included in this evaluation are shown 
in table 8. The figures include all costs to get the fiber from 
the mill to the customer's fabricating plant. Truck, rail, and 
ocean freight charges, as well as handling, insurance, ware- 
housing, port fees, and marketing commissions, are in- 
cluded. The table includes costs of transportation from the 
amosite and crocidolite fields of southern Africa to the 
various regions. Although fiber is not presently transported 
in appreciable quantities to these areas, the deposits are 
the only commercially available source of these fiber types. 



Table 7.— Market distribution of asbestos producers (2) 

Portion to destination, % 

1981 production, North Central and Africa and 

Source 10 3 t America 1 South America 2 Europe 3 Middle East 4 

Australia 44.6 4 9 

Brazil 138.4 100 

Canada: 

Eastern 1,032.0 37 10 24 7 

Western 90.0 21 8 29 5 

Cyprus 34.3 65 

Greece 100.0 40 40 

Italy 137.1 100 

South Africa: 

Northern Cape 102.3 10 30 

Northern Transvaal 56.8 100 

Eastern Transvaal 6 76.8 7 16 5 

Zimbabwe 247.6 47 13 20 

Wajor consuming centers for Canadian fiber are New York, Toronto, and Montreal; major consuming center for all other fiber is New York. 

2 Major consuming centers are Mexico, Colombia, and Brazil. 

3 Major consuming centers are France, the Federal Republic of Germany, and Belgium. 

4 Major consuming centers in the Mediterranean area are Egypt and Saudi Arabia. 

5 Major consuming centers are Japan and South Korea. 

includes Swaziland. 



Asia 5 



87 


22 
37 
35 
20 


60 



72 

20 



15 



Table 8.— Estimated mill to market fiber transportation costs 

Cost to destination (January 1982 $/t) 

Source North Central and Africa and 

America' South America 2 Europe 3 Middle East 4 Asia 5 

Australia 90 120 80 

Brazil 60 

Canada: 

Eastern 50 80 120 130 210 

Western 210 190 250 270 180 

Cyprus 1 00 80 

Greece 80 80 130 

Italy 50 

South Africa: 

Northern Cape 130 180 160 100 150 

Northern Transvaal 80 130 110 40 10l 1 ' 

Eastern Transvaal 6 80 130 120 50 100 

Zimbabwe 100 150 140 70 130 

'Major consuming centers for Canadian asbestos are New York, Toronto, and Montreal; major consuming center for all other fiber is New Yo'rk. 
2 Major consuming centers are Mexico. Colombia, and Brazil. 

3 Major consuming centers are France, the Federal Republic of Germany, and Belgium. k 

*Major consuming centers in the Mediterranean area are Egypt and Saudi Arabia; for South African deposits, figures presented reflect transportation to internal 
markets only. 
'Major consuming centers are Japan and South Korea, 
includes Swaziland i 



The lowest cost shown is $40/t, the cost of internal 
transportation from the northern Transvaal to internal 
markets in southern Africa. The highest transportation 
costs are associated with transportation of fiber from the 



Cassiar deposit in northern British Columbia to the vt nous 
regions. A substantial portion of these high coses is 
associated with transporting the fiber from the mine to port 
near Vancouver. 



EVALUATION METHODOLOGY 



An economic evaluation of each property provides an 
estimate of the average total cost of production for the opera- 
tion over its estimated producing life. The evaluation uses 
discounted cash flow rate of return (DCFROR) techniques 
to establish the constant-dollar long-run price at which the 
asbestos fiber would need to be sold so that revenues are 
sufficient to cover all costs of production, including a 
prespecified rate of return on investment. In the price pro- 
portioning routine used in this evaluation, for each deposit, 
costs are burdened against total revenues required to meet 
the target rate of return. Then, revenues are assigned to 
the various products (i.e., fiber grades) according to the price 
proportions of those grades. In this manner, the burden of 
the cost of production for the deposit is not allocated to only 
one commodity, but is allocated among all commodities 
based on the price proportions of those commodities. This 
method is especially useful for operations producing com- 
modities for which there is not a clearly defined primary 
product. It is the most appropriate method for determining 
costs for properties that produce commodities whose prices 
tend to vary in relation to one another. 

The basis for establishing the price proportions for this 
evaluation was the January 1982 producer or posted prices 
quoted by Asbestos magazine (table 3); an analysis of pro- 
ducer prices during 1974-83 revealed that the relative 
prices of grades 3 through 8 remained very nearly constant, 
so that the January 1982 price ratios are representative of 
a reasonably long historical trend. Although actual and 
relative values of fiber grades may vary through time ac- 
cording to negotiated contracts, the price ratios based on 
January 1982 producer prices are representative of the long- 
term relative prices of the various fiber grades. 

An implicit assumption in this evaluation is that each 
property represents a separate corporate entity, with neg- 



ative cash flows in the developmental stage of a property 
carried forward in time as tax losses, rather than being ap- 
plied against other corporate revenues in the year they 
occur. 

All capital investments incurred 15 yr or more prior to 
the date of this analysis (January 1982) are considered to 
be totally depreciated. Investments incurred after 1968 hav ■ 
the undepreciated balances entered as an expenditure in 
January 1982. All subsequent investments, reinvestments, 
operating costs, and transportation costs are expressed in 
constant January 1982 dollars and entered in the year they 
have been projected to occur. 

The life of each property was estimated by using the best 
available information to determine a likely future annual 
production rate, applied against the demonstrated resource 
of the property. The relatively depressed market conditions 
that have prevailed in the asbestos industry during the past 
few years have resulted in temporary closures o r reduced 
capacities at several operations. For purposes of the avail- 
ability discussion, operations that have produced in the past 
but were not operating at the time of this evaluation 
(January 1982) have been considered to be nonpnyiucers; 
they have been identified as past producers on table 4. Giyen 
the current and likely near-term future market conditions, 
none of these properties is likely to come back into produc- 
tion in the near future. 

Operations that have reduced capacity from past higher 
levels owing to recent depressed market conditions have 
been assumed to maintain production at the present (re- 
duced) capacity if there was information available to sup- 
port that assumption. Annual production averagod over the 
life of each property that has been assumed for this evalua- 
tion are shown in table 5. 

Two separate analyses were performed for this evalua- 



16 



tion with alternative target rates of return on investment 
specified. Average total cost of production for each fiber 
grade produced over the life of each property was estimated 
with a 0% and 15% DCFROR. The 0% is used to evaluate 
the "breakeven" cost where revenues are sufficient to 
recover total investment and production costs over the 



operation's life but provide no profit. For privately owned 
enterprises or those not strictly developmental in nature, 
a reasonable economic decisionmaking parameter is repre- 
sented by the 15% DCFROR. This rate was considered the 
minimum return sufficient to maintain adequate long-term 
profitability and attract new capital to the industry. 



AVAILABILITY 



The amount of chrysotile asbestos fiber potentially 
available from evaluated properties for grades 3 through 
7 filler, by grade, is shown on the graphs in this section. 
Dat'. for each fiber grade are presented on total availabil- 
ity curves for all properties evaluated and on annual avail- 
ability curves for producers. Since only one property con- 
tain s grade 2 and one property contains grade 8 fiber, no 
curves ,r discussions of costs are included for those grades. 
Crocidolite and amosite availability are discussed in a sepa- 
rate section. 

On the total availability curves, properties that do or could 
produce fiber of the grade shown are ranked in order of 
increasing average total cost of production. Nearly all prop- 
ertie- contain more than one fiber grade, so that most 
properties occur on more than one curve. The cost of pro- 
ducing each fiber grade at a given property has been deter- 
mined according to the price proportioning routine described 
earlier in this report. 

Ihe costs on the total availability curves are presented 
in terms of 0% and 15% DCFROR at the mill. The at-mill 
cost is useful in comparing production costs among the prop- 
■ rties and is the basis for the weighted average cost figures 
end cost discussion in this section of the report. The 0% ROR 
cost rppresents the breakeven cost of production, or the price 
of fiber necessary to cover operating and capital costs, but 
no profit. 

The annual availability curves are not intended to pre- 
sent the Bureau of Mines prediction of how much fiber of 
e^ch grade will be produced in the future; thus, they should 
not be interpreted as supply curves. The intent is to show 
how much fiber could be produced at a given cost from prop- 
erties that were actually produced at the time of this evalua- 
tion (January 1982). To accomplish this, assumptions re- 
garding most likely future annual production were 
necessary. 



CHRYSOTILE, GRADE 3 

Evaluated properties that do or could produce chrysotile 
fiber of grade 3 are listed below. Nonproducers are marked 
with an asterisk (*): 

Canada.— Bell, Black Lake, British Canadian, Cassiar, 
King-Reaver, National, Penhale.* 

Other.— Amiandos (Greece), El Dorado* (United States), 
Lowell (United States), Shabanie (Zimbabwe). 

Of the 11 properties that contain grade 3 chrysotile fiber, 
9 could produce at a cost (15% DCFROR, f.o.b. mill) equal 
to or lower than the January 1982 price of $l,478/t (fig. 7). 
The total amount of grade 3 chrysotile fiber potentially 
available from all properties is 1.59 million t, 97% (1.54 
million t) of which is contained in the nine properties that 
have a cos' equal to or lower than the January 1982 price. 

The weighted average f.o.b. mill cost (15% DCFROR) for 
the six Canadian chrysotile producers is $976/t. Amiandos 




TOTAL RECOVERABLE ASBESTOS GRADE 3, I0 6 t 

Figure 7. — Total availability, grade 3 chrysotile. 

(Greece) and Shabanie (Zimbabwe) are among the lowest 
cost properties, and the two U.S. properties (Lowell and El 
Dorado) are among the highest. 

In terms of annual availability (fig. 8), there is little dif- 
ference in the amount of fiber potentially available at costs 
(15% DCFROR, f.o.b. mill) equal to or lower than the 
January 1982 price, or at costs 25% higher ($l,850/t) or 
lower ($l,100/t) than the January 1982 price. The amount 
of fiber potentially available at all costs annually ranges 
from 84,300 1 in 1987-89 to less than 58,000 t in 2000. The 
total amount of grade 3 chrysotile fiber potentially available 
in 1987 at a cost equal to or less than the January 1982 
price of $l,478/t from producing properties is 81,500 t, or 
approximately 97% of the total amount potentially available 
from all producers evaluated. At costs less than or equal 
to half of the January 1982 price ($740/t), the amount of 



1 1 
Price, Jan. 1982 $/t 




1 1 


1 




. 




\ 


/■/ 


"---. 






0-$l,IOO 








\\o-$ 1,650 - 
0-$ 1,478 








\ 


~ 






~ 




1 1 


\0-$740 





» 1986 1988 1990 1992 1994 1996 1998 2000 

Figure 8. — Annual availability, grade 3 chrysotile. 



17 



fiber potentially available in 1987 from chrysotile producers 
is 43.000 t. 

Tbe two nonproducers could add only a small amount of 
grade 3 chrysotile fiber annually. Together, they could ac- 
count for an additional 6.200 t in 1987. decreasing to 5,800 
t in 2000 if they were brought into production by the 
mid-1980's. 



CHRYSOTILE, GRADE 4 

All but 6 of the 33 chrysotile properties evaluated con- 
tain grade 4 fiber. Only Santa Rita and Christie (United 
States*. Msauli and Senekal (South Africa). Pegaso (Mex- 
ico), and Roberge Lake (Canada) do not. Those that do are 
listed below, with nonproducers identified by an asterisk (*): 

Canada.— Abitibi.* Asbestos Hill. Baie Verte, Bell, Black 
Lake, British Canadian, Carey Canada, Cassiar, Jeffrey, 
King-Beaver. Midlothian,* National. Penhale.* 

United States.— Calaveras, El Dorado,* Lowell, Slate 
Creek.* 

Zimbabwe,— Gath's. King, Shabanie. 

Other.— Amiandos (Greece). Balangero (Italy), Cana Brava 
(Brazil). Las Brisas (Colombia), Havelock (Swaziland), 
Woodsreef (Australia), Zidani (Greece). 

At costs of production (15% DCFROR. f.o.b. mill) equal 
to or less than the January 1982 price ($974/t), there are 
23 properties containing 20.40 million t of grade 4 fiber, 
or 979 of the total contained in all 33 chrysotile properties 
evaluated (fig. 9). Nonproducers account for 4.21 million t, 
or 219 of the group 4 fiber contained in all chrysotile prop- 
erties evaluated. The weighted average f.o.b. mill cost (15% 
DCFROR I for Canadian producers, containing 11.42 million 
t, is $626 t. 

In terms of potential annual availability (fig. 10), the 
peak year is 1990. when 674,000 t of grade 4 chrysotile fiber 
could be supplied by producers. Nonproducers could add 
167.000 t to this total. Of the total of 841,000 t potentially 
available from producers and nonproducers in 1990, 
805,000 t could be produced at an f.o.b. mill cost (15% 
DCFROR i equal to or less than the January 1982 price of 
$974 t. 

In 1990, the two undeveloped deposits (Abitibi and 
Penhale' and one past producer (Midlothian), all in Canada, 
account for only 38,000 t. 



i'X 



ZJXC- 

1,800- 

T ax '~ 

- 1,400- 

. .200- 

g HE 

< 900- 

6O0 - 



K£r 

• 5-;- 

D)-pc1 



J 



« « H 10 12 14 16 18 

IOIM ~ : ' 7/ERABLE ASBESTOS GRADE A. tO*1 

Figure 9.— Total availability, grade 4 chrysotile. 




Price, Jon I982 $/t 



..0-$730 



i $490 



I998 20O0 



Figure 10.— Annual availability, grade 4 chrysotile. 



CHRYSOTILE, GRADE 5 

Twenty-seven (21 producers, 6 nonproducers) of the 42 
properties evaluated do or could produce fiber of grade 5. 
The total amount of grade 5 fiber potentially available from 
all chrysotile properties is 16.74 million t (fig. 11). At an 
f.o.b. mill cost (15% DCFROR) equal to or less than the 
January 1982 price of $574/t, 13.61 million t is potentially 
available from 21 properties. Four of the six most costly 
properties are nonproducers. Properties that contain grade 
5 fiber are listed below, with nonproducers identified by an 
asterisk (*): 

Canada.— Abitibi*, Asbestos Hill, Baie Verte, Bell, 
Black Lake, British Canadian, Carey Canada, Cassiar, Jef- 
frey, King-Beaver, Midlothian,* National, Penhale,* 
Roberge Lake.* 

Zimbabwe.— Gath's, King, Shabanie. 

South Africa.— Msauli, Senekal.* 

Other.— Balangero (Italy), Calaveras (United States), 
Cana Brava (Brazil), Havelock (Swaziland), Lowell (United 
States), Pegaso* (Mexico), Woodsreef (Australia), Zidani 
(Greece). 

The weighted average cost of production (15% DCFROR, 
f.o.b. mill) for all Canadian properties, containing a total 
of 8.83 million t of grade 5 fiber, is $390/t. For the 10 Cana- 
dian producers, the weighted average cost is $365/t. These 
10 properties account for 5.81 million t, or 35% of the total 
grade 5 chrysotile fiber contained in all properties 
evaluated. Including nonproducers, Canada accounts for 
53% of the total. The three Zimbabwean properties contain 
1.67 million t, or 10% of the total, and could be produced 
at a weighted average cost of $238/t. 

The annual availability curve (fig. 12) shows a relatively 
stable potential production rate over the 1984-2000 period. 
The maximum annual production level from producers at 
an f.o.b. mill cost (15% DCFROR) equal to or lower than 
the January 1982 price of $547/t is 479,000 t in 1987. Of 
the total amount potentially available in 1987, 202,000 t 
is contained in producing Canadian properties. The 
minimum annual potential production over the 1984-2000 
period is 393,000 t in 2000, reflecting the apparent exhaus- 
tion of demonstrated resources at several properties. 

Canadian nonproducers could contribute an annual 
average of 97,000 t of chrysotile, but only 24,000 t would 
be available at a cost lower than $500/t. At $547, the 
January 1982 producer price for grade 5, less than 10,000 t 
of chrysotile could be produced from the Canadian 
nonproducers. 



18 



,400 




1 1 

KEY 
15-pct 


-T" 1 


1 i i i 


,200 




0-pct 






_]_ - 


,000 


- 










1 








r J 


800 














600 












. 










r r 










1 ' 

J \ 




400 




J 










_y \i- 






.-r 


__ --i 








i i .- 


III. 



TOTAL RECOVERABLE ASBESTOS GRADE 5, I0 5 t 



Figure 1 1 .—Total availability, grade 5 chrysotile. 



450 




p 


ice 


T 

Jon 


I982 $/t 






— r 


1 




- 1 1 1 

0-$8B5 


" 


















400 




0-$547 "~-~"^; 


350 




- 


300 






















" 


250 


- 






















- 


200 
























" 


1 50 
























" 


I00 






















0-$275 


- 


SO 















L 






-J 1 1 


" 



1998 2000 



Figure 12. — Annual availability, grade 5 chrysotile. 



CHRYSOTILE, GRADE 6 

All properties evaluated that contain chrysotile fiber 
of grade 6 are listed below, with nonproducers identified 
by an asterisk (*): 

Canada.— Abitibi,* Baie Verte, Bell, Black Lake, British 
Canadian, Carey Canada, Cassiar, Jeffrey, King-Beaver, 
Midlothian,* National, Penhale,* Roberge Lake.* 

South Africa. — Msauli, Pomfret, Senekal.* 

Other.— Balangero (Italy), Calaveras (United States), 
Cana Brava (Brazil), Las Brisas (Colombia), Lowell (United 
States), Pegaso* (Mexico), Shabanie (Zimbabwe), Woodsreef 
(Australia), Zidani (Greece). 

There are 12.84 million t of grade 6 chrysotile fiber 
potentially available from 19 properties with f.o.b. mill costs 
(15% DCFROR) equal to or lower than the January 1982 
price of $386/t (fig. 13). Seventeen of the 19 properties are 
producers. The weighted average cost of production for 
Canadian producers is $270/t. These nine properties account 
for 7.06 million t, or 55% of total grade 6 fiber contained 
in all chrysotile properties evaluated. Including the four 
nonproducers, Canadian properties contain 9.91 million t. 
The weighted average cost for the four Canadian chrysotile 
nonproducers is $579/t. 

At costs (15% DCFROR, f.o.b. mill) equal to or less than 
the January 1982 price, the amount of grade 6 fiber poten- 
tially available from producers between 1984 and 2000 is 



KEY 

■ 15-pct 

0-pct 



,-- J 



TOTAL RECOVERABLE AS8EST0S GRAOE 6, I0 6 t 

Figure 13.— Total availability, grade 6 chrysotile. 



at a peak of 470,000 t in 1986-88 and gradually declines 
to 318,000 t in 2000 (fig. 14). The amount of grade 6 fiber 
potentially available in 1987 at costs lower than or equal 
to the January 1982 price (431,000 1) represents 92% of total 
production potential from producers in that year. 

The six nonproducers could add a maximum of 22,000 t 
by 1987 at costs less than or equal to the January 1982 



450 
400 



Price, Jon. 1982 $/t 



T 1 1 1 r 



V 



-\ 



0-$l95 



1998 2000 



Figure 14.— Annual availability, grade 6 chrysotile. 



19 



price. The average annual availability from Canadian non- 
producers is nearly 130.000 t. of which 60.000 t would have 
a cost lower than or equal to the January 19S2 producer 
price of S3S6 t. The two other grade 6 nonproducers. Senekal 
and Pegaso. could account for an additional 26.000 t. 



CHRYSOTILE. GRADE 7 



Canada. Potential annual availability at costs less than or 
equal to $175't decreases to 320,000 t in the late 1990's; 
total annual production potential (at all costs) is 321,000 t 
in 2000. 

Nonproducers could account for 60,000 to 70,000 t by 
the late 1980's, and as much as 147,000 t by 2000, resulting 
in no decrease in annual production from current levels. 



The following 20 properties contain grade 7 chrysotile 
fiber. Nonproducers are identified with an asterisk (*): 

Canada. -Abitibi." Asbestos Hill. Bell. Black Lake. 
Carey Canada. Jeffrey. King-Beaver. Midlothian.* Na- 
tional. Penhale." Roberge Lake.* 

L'nited States.— Christie.* El Dorado,* Lowell, Santa 
Rita. 

Otaer.— Balangero (Italy). Msauli and Senekal* (South 
Africa'. Pegaso* (Mexico), Woodsreef (Australia). 

Of the properties listed above. 11 (7 producers, 4 non- 
producers' are located in Canada. However, the grade 7 
chrysotile resource from Canada is overshadowed by that 
contained in the New Idria intrusive in California, which 
for all practical purposes is unlimited. For this evaluation, 
only 126 yr of production potential at Santa Rita are 
included. 

It is not possible to present a total availability curve 
for grade 7 chrysotile fiber since the costs associated with 
one or more properties would be disclosed. The total amount 
of grade 7 fiber contained in all chrysotile properties is 19.27 
million t. 15.79 million t of which is contained in produc- 
ing properties. At f.o.b. mill costs 1 15 r ; DCFRORi equal to 
or lower than the January 1982 price of $175 t, there are 
17.16 million t potentially available from 12 properties (9 
in Canada. 7 of which are producers). The weighted average 
cost for the seven Canadian producers is $125/t, a figure 
that is heavily influenced by the Jeffrey operation, which 
accounts for approximately two-thirds of the total grade 7 
chrysotile resource in all Canadian producers, and for 55% 
in all Canadian properties evaluated. 

The amount of grade 7 fiber potentially available an- 
nually from producers (fig. 15 1 at f.o.b. mill costs equal to 
or lower than the January 1982 price of $175>t peaks at 
403.000 t in 1985. The drop in production potential to 
336.000 t in 1993 largely reflects the apparent exhaustion 
of demonstrated resources of the National property in 



- - - | ■ 

«oot- „ 






Figure 15.— Annual availability, grade 7 chrysotile. 



AMOSITE AND CROCIDOLITE 

Only one property, Penge, produces amosite, and only 
eight properties contain crocidolite. Six of the eight 
crocidolite properties are owned by one company, Gefco, and 
Gefco acts as the sole marketing agent for all crocidolite 
produced in the Republic of South Africa. For these reasons, 
availability curves for amosite and crocidolite could not be 
shown in this report. The following discussion, however, 
presents relevant general information concerning these 
fiber types in terms of total and annual availability. 

The Penge Mine is virtually the only current source for 
amosite, producing over 40,000 t annually of relatively long 
fiber (equivalent to grades 3 and 4 in the Quebec grading 
system). Present demonstrated resources at Penge are ap- 
proximately 800,000 t, sufficient to 'last through the end 
of this century at current rates of production. In addition, 
there is a resource of possibly more than 3 million t of poten- 
tially recoverable fiber that is currently inaccessible due 
to high water inflows. 

Eight South African crocidolite properties were 
evaluated, six of which were producers at the time of this 
evaluation (January 1982). The total amount of crocidolite 
fiber (in terms of fiber length, roughly equivalent to grades 
3 and 4 in the Quebec grading system) is 1.69 million t in 
all eight properties evaluated. The weighted average f.o.b. 
mill cost (15% DCFROR) of production has been estimated 
to be $422/t. 

The eight crocidolite properties have a combined annual 
production potential (averaged over the life of each prop- 
erty) of approximately 132,000 t. Total world crocidolite pro- 
duction (all from the northern Cape, in the Republic of South 
Africa, including Bophuthatswana) in 1980 and 1981 was 
about 134,000 t, but declined to 112,000 t in 1982. 
Crocidolite production from mines in the Republic of South 
Africa was less than 100,000 t in that year. The two past 
producers, Danielskuil and Riries, have a combined average 
annual production potential of more than 21,000 t. Gener- 
ally, the crocidolite deposits of the northern Cape are rela- 
tively small and thus do not have large demonstrated 
resources. The average size of the eight properties evaluated 
for this study is 211,000 t. Because of their relatively small 
size, each individual crocidolite occurrence cannot be ex- 
pected to have a long production life; thus, potential annual 
availability analyses of this evaluation resulted in a steep 
decline by the early 1990's, when several of the properties 
will have exhausted their currently demonstrated resources. 
However, as noted earlier in this report, there is in general 
a favorable potential for discovery of additional deposits in 
the northern Cape, and it cannot be concluded that poten- 
tial annual availability of crocidolite fiber will be severely 
reduced before the end of the century. 



20 



AVAILABILITY SUMMARY 



Table 9 is a summary of asbestos availability for chrysotile 
fiber of grades 3 through 7. Total and annual potential 
availability are shown at 15% DCFROR costs equal to or 
lower than the January 1982 prices for each grade, and at 
costs equal to or lower than +25%, and —25% and —50% 
of January 1982 prices. 

For all grades of chrysotile, nearly all fiber contained in 
all properties evaluated is potentially available at costs 
equal to or lower than +25% of the January 1982 prices. 
For all but grade 3, the amount of fiber potentially available 
at costs equal to or lower than —25% and —50% of the 
January 1982 prices is dramatically less than that available 
at costs equal to or lower than the January 1982 prices. 

The situation is similar in terms of 1985 annual availabil- 
ity, although caution is advised since annual availability 
figures derived as a result of this evaluation are based on 
certain assumptions regarding likely future production 
levels. However, 1985 is sufficiently near term that the an- 
nual production figures from properties that were in opera- 
tion in January 1982 should not differ substantially from 
present levels. A "typical" annual availability curve based 



on this evaluation shows declining annual availability over 
time owing to apparent depletion of demonstrated resources 
from producing properties. However, most of the properties 
evaluated have additional resources at lower levels of prob- 
ability so that potential annual availability should not 
decline substantially within the foreseeable future. 

Demonstrated resources of amosite fiber at the Penge 
property are sufficient to sustain annual production at the 
current level of 40,000 t/yr through 2000. An additional 3 
million t of recoverable fiber is currently inaccessible 
because of water inflow but could become an important re- 
source in the future. Currently demonstrated resources of 
crocidolite in the eight properties evaluated are generally 
small, and annual availability based on those resources is 
projected to decline precipitously by the early 1990's owing 
to exhaustion of resources at several of the properties. 
However, the potential for discovery of additional resources 
in the northern Cape crocidolite field is favorable, and the 
apparent decline in production potential probably is not an 
accurate representation of potential availability of this fiber 
type. 



Table 9. — Chrysotile availability summary, 1 thousand metric tons 

Grade 3 4 5 

Number of properties: 

Producing 9 23 21 

Nonproducing 2 4 6 

Available fiber: 

Total 1,586 21,002 16,742 

1985 76 685 483 

Available fiber, based on costs = Jan. 1982 prices (P): 
Total: 

At 100% P 1,539 21,002 13,613 

At 125% P 1 ,585 20,470 14,932 

At 75% P 1 ,459 9,987 8,320 

At 50% P 794 3,825 1 ,533 

1985: 

At 100% P 74 677 446 

At 125% P 76 680 453 

At 75% P 68 450 334 

At 50% P 43 171 71 

'Based on total demonstrated resources, regardless of cost. 



19 


12 


6 


8 


15,536 


19,268 


462 


403 


12,840 


17,156 


13,618 


17,758 


6,023 


4,525 


1,067 





424 


381 


426 


395 


268 


183 


46 






CONCLUSIONS 



The results of this analysis suggest that, in terms of total 
availability, demonstrated recoverable chrysotile fiber in 
properties evaluated appears to be adequate to sustain cur- 
rent production levels well into the next century. It was not 
possible to compare the annual availability results with 
actual world or market economy country production and de- 
mand projections on an individual grade basis owing to the 
paucity of published data. However, the annual figures pre- 
sented in this report for the early years of the analysis are 
a reasonable estimate of recent production levels from the 
major producing operations in market economy countries. 

In general, the amounts of chrysotile fiber of grades 3 
through 7 potentially available on an annual basis are pro- 
jected to decline at a relatively slow rate by the end of the 
century owing to the apparent exhaustion of demonstrated 
resources at some properties. However, most of the proper- 
ties evaluated have substantial additional resources at 
lower levels of probability, and long-term adequacy of 
chrysotile fiber of grades 3 through 7 is assured. 



The potential availability of grade 2 chrysotile fiber could 
be a matter of some concern. At the time of this evaluation, 
only one property, Shabanie (Zimbabwe), was known to con- 
tain a significant amount of recoverable grade 2 fiber. Ow- 
ing to its value for use as spinning-grade fiber, its limited 
geographical occurrence in relatively small amounts could 
be a matter of concern to present and potential users of the 
fiber. Only one property, Balangero (Italy), produces grade 
8 fiber, but grade 8 has limited application and is of little 
value; consequently, its apparent low potential availabil- 
ity is not of major importance. 

Although currently demonstrated resources of crocidolite 
in the eight evaluated properties are relatively small, the 
potential for discovery and development of other deposits 
in the northern Cape field appears good, and long-term 
availability of crocidolite fiber is probably not in jeopardy. 
The Penge property should be able to provide adequate 
amounts of amosite fiber from currently demonstrated 
resources at least through the end of the century, and for 



21 



a long time beyond if recovery of presently inaccessible 
resources proves viable in the future. 

In view of the generally depressed state of the asbestos 
industry during the past several years, in part resulting 
from the growing concern relating to potential health 



hazards associated with the exploitation and use of asbestos 
fiber, it appears likely that factors other than geologic 
availability of fiber will have the largest impact on the long- 
term viability of the industry. 



REFERENCES 



1. Clifton, R.A. Asbestos. Ch. in Mineral Facts and Prob- 
lems. 1980 Edition. BuMines B 671. 1981, pp. 55- 
71. 

2. . Asbestos. Ch. in BuMines Minerals Yearbook 

1982. v. 1. pp. 103-111. 

3. Energy. Mines and Resources Canada. Asbestos. 
Miner. Bull*. MR 155. 1976. 26 pp. 

4. Clarke. G. Asbestos— a Versatile Mineral Under 
Siege. Ind. Miner., No. 174, Mar. 1982, p. 19-37. 

5. Todd, J.C. Asbestos. Eng. and Min. J., v. 185, No. 3, 
Mar. 1984. pp. 88-89. 

6. Clifton. R.A. Asbestos. Sec. in BuMines Mineral Com- 
modity Summaries 1984, pp. 12-13. 

7. Mining Magazine (London). Pomfret Asbestos Mine. 
Sept. 1983. pp. 153-159. 



8. Asbestos. Current Asbestos Prices. V. 63, No. 7, Jan. 
1982, pp. 40-41. 

9. U.S. Geological Survey and U.S. Bureau of Mines. 
Principles of a Resource/Reserve Classification for Minerals. 
U.S. Geol. Surv. Circ. 831, 1980, 5 pp. 

10. Industrial Minerals. Woodsreef Asbestos Mine To Re- 
open. No. 200, May 1984, p. 15. 

11. Sassos, M.P. Greece Gears for a 100,000-mt/yr Rate 
From Its First Asbestos Complex. Eng. and Min. J., v. 184, 
No. 4, Apr. 1983, pp. 66-67. 

12. Shride, A.F. Asbestos. Ch. in United States Mineral 
Resources. U.S. Geol. Survey Prof. Paper 820, 1973, pp. 
63-73. 

13. Mining Journal (London). Alaska. V. 393, No. 7712, 
June 10, 1983, p. 393. 



»U.S. GOVERNMENT PRINTING OFFICE : 1985 0-4-81-256/32597 



■A 




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